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Map showing Earth's principal tectonic plates and their boundaries in detail. These plates comprise the bulk of the continents and the Pacific Ocean.For purposes of this list, a major plate is any plate with an area greater than 20 million km 2 (7.7 million sq mi)
Plate tectonics on Earth is hypothesized to be driven by “slab pull,” where the sinking of the more dense subducting plate provides the spreading force for mid-ocean ridges. [112] “Ridge push” is comparatively weak in Earth's plate tectonics. [112] Extensional features are abundant on icy moons, but compressional features are sparse. [112]
Plate tectonics was a suitable explanation for seafloor spreading, and the acceptance of plate tectonics by the majority of geologists resulted in a major paradigm shift in geological thinking. It is estimated that along Earth's mid-ocean ridges every year 2.7 km 2 (1.0 sq mi) of new seafloor is formed by this process. [50]
The Pacific plate and other principal plates of Earth's lithosphere. The Pacific plate is an oceanic tectonic plate that lies beneath the Pacific Ocean.At 103 million km 2 (40 million sq mi), it is the largest tectonic plate.
Crustal material at the western edge of the Pacific plate is some of the oldest oceanic crust on Earth (up to 170 million years old), and is, therefore, cooler and denser; hence its great height difference relative to the higher-riding (and younger) Mariana plate. The deepest area at the plate boundary is the Mariana Trench proper.
The colours indicate the age of oceanic crust, wherein lighter indicates younger age, and darker indicates older age. The lines represent tectonic plate boundaries. Continental and oceanic crust on the Earth's upper mantle. Oceanic crust is the uppermost layer of the oceanic portion of the tectonic plates.
The Caribbean plate is a mostly oceanic tectonic plate underlying Central America and the Caribbean Sea off the northern coast of South America. Roughly 3.2 million square kilometres (1.2 million square miles) in area, the Caribbean plate borders the North American plate , the South American plate , the Nazca plate and the Cocos plate .
The Farallon plate subducted under North America from the late Mesozoic, while spreading between the Pacific and Farallon plates was initiated 190 Ma and lasted until the break-up of the Farallon plate 23 Ma. During the Cenozoic the Farallon plate broke up along the eastern Pacific margin into the Kula, Vancouver/Juan de Fuca, and Cocos plates.